a heart attack caused by a clot, one that could be fatal. but plavix helps save lives. plavix taken with other heart medicines, goes beyond what other heart medicines do alone, to provide greater protection against heart attack or stroke and even death by helping to keep blood platelets from sticking together and forming clots. ask your doctor about plavix. protection that helps save lives. people with stomach ulcers or other conditions that cause bleeding should not use plavix. taking plavix alone or with some other medicines including aspirin may increase bleeding risk, so tell your doctor when planning surgery. certain genetic factors and some medicines, such as prilosec, may affect how plavix works. tell your doctor all the medicines you take, including aspirin, especially if you've had a stroke. if fever, unexplained weakness or confusion develops, tell your doctor promptly. these may be signs of ttp, a rare but potentially life-threatening condition reported sometimes less than 2 weeks after starting plavix. other rare but serious side effects may occur.